Basics Of Pharmacy: Classification Of Crude Drugs

Sunday, December 5, 2021

Classification Of Crude Drugs

Crude drugs are those substances that are obtained from natural sources and are used for treatment or prevention of different diseases without chemical modification of these substances. Mean crude drugs are used in natural form without any modification.

Classification Of Crude Drugs

In this article, we will discuss the classification system used to classify the crude drugs obtained from plants and we use the following classification system,

  • Alphabetical Classification

  • Taxonomical Classification

  • Morphological Classification

  • Pharmacological Classification

  • Chemical Classification

  • Chemotaxonomic Classification

  • Sero Taxonomic Classification

Alphabetical Classification

  • It is a basic and simple method of classification used to classify crude drugs. As the name indicates this classification system is based on arranging the drugs depending on Alphabets of their name usually English or Latin common names are used

Books For Classification 

Following books are used as reference books for this system of classification

  • British Pharmacopoeia

  • British Herbal Pharmacopoeia

  • British Pharmaceutical Codex

  • United States Pharmacopoeia

  • Indian Pharmacopoeia

  • European Pharmacopoeia


  • One important note is that in European pharmacopoeia the crude drugs are classified according to their Latin names and in British Pharmacopoeia and British pharmaceutical codex these drugs are classified according to their English names.


  • Aloe

  • Benzoin

  • Cinchona

  • Dill

  • Ergot

  • Fennel

Taxonomical Classification

As we know that for all plants the kingdom is Plantae.

According to the taxonomic classification system the crude drugs are classified according to the following system,

  • Class

  • Subclass

  • Superorder

  • Order

  • Family

  • Subfamily

  • Tribe

  • Subtribe

  • Genus

  • Species

  • Variety

  • Form

  • Cultivar


The crude drugs are classified into two classes as follow,

  • Angiosperms

  • Gymnosperms

    • Angiosperms are those plants which produce flowers.

    • Gymnosperms are those plants that do not produce flowers.


Based on seed leaves the plants are classified into two subclasses Monocots and Dicots.

Monocots are those which have one seed leaf and dicots are those which have two seed leaves.


  • In superorder, all the plants are grouped according to their related families and it is believed that all plants in superorder develop variations that arise from the same ancestor.

  • Dicots have six superorders and monocots have four superorders.

  • At the end of the superorder name, we always see "idae"


  • Magnoliidae

  • Alismatidae


  • The superorder is further divided into many orders and the name ends with "ales"


  • The order is further divided into families. In a family, plants have many common features. The family ends with "aceae"


  • The family is further divided into subfamilies and the name of subfamily ends with "ideas"


  • Within a family, plants are classified into tribes depending on small botanical differences and end with "eae"


  • Tribes are further classified into subtribes depending on such small differences which can only be differentiated by the botanist.


  • In Genus plants are recognized by the common plant name.


  • The species of a plant describe individual plants and name represent the colour of the flower, size and shape of a leaf or the place where it was found the first time.


  • A variety is a plant that has only minute differences from the species.


  • Form is a plant that has a change in colour of a flower or the size of a leaf from the species.


  • A cultivar describes how a plant is cultivated means either by vegetative or non-vegetative type of propagation.

Morphological Classification

In morphological classification, the crude drugs are classified based on the morphology of the plant,means the visible appearance of the plants.

In this system of classification, the crude drugs are classified into the following two main types,

  • Organized Drugs

  • Unorganized Drugs

Organized Drugs

  • Those drugs which are obtained directly from plant parts and have a cellular structure like leaves, roots etc are known as organized drugs.

Examples Of Organized Drugs

Following are some main examples of organized drugs,


  • Sandalwood

  • Red sandalwood 


  • Digitalis leaves

  • Mint leaves

  • Tulsi leaves

  • Tea leaves


  • Cinchona bark

  • Cinnamon bark

Flowering Parts

  • Clove

  • Safrone

Roots And Rhizomes

  • Ginger

  • Garlic

  • Glycyrrhiza

  • Turmeric


  • Cardamom

  • Amla

  • Anise

  • Fennel

  • Coriander


  • Black mustard

  • White mustard

  • Espagnol

Hair & Fibers

  • Cotton

  • Silk

Plants & herbs

  • Ergot

  • Ephedra

Unorganized Drugs

  • The drugs which are obtained from plants and are prepared by some physical modifications like drying or extraction are known as unorganized drugs and these do not contain any cellular parts of the plant.


Following are some main examples of unorganized drugs,


  • Acacia

  • Tragacanth

  • Guar gum


  • Benzoin 

  • Tar

  • Coal tar

Volatile Oils

  • Peppermint Oil

  • Anise Oil

  • Lemon Oil

  • Clove Oil

Dried latex

Dried juice

Pharmacological Classification

  • In the pharmacological classification system, the crude drugs are classified according to the pharmacological action of constituents present in plants.

  • In this system of classification, the crude drugs are classified only on their action rather than their appearance, shape or taxonomy.


Following are some main examples,

G.I.T Drugs

This class contains all the drugs which affect G.I.T and  maybe carminative, antiemetic, laxative, purgative etc and include following,

  • Espagnol

  • Senna

  • Ipecac

  • Castor Oil

  • Fennel

  • Cardamom

Respiratory Drugs

This class contain all the drugs in which constituents affect the respiratory tract and may be expectorants, Bronchodilators or antitussive and includes the following,

  • Liquorice

  • Tea

  • Ephedra

CVS Drugs

This class contains drugs that affect the cardiovascular system and may be cardiotonic, Antihypertensive, Vasoconstrictors etc.

Includes following,

  • Digitalis

  • Squill

  • Ergot

Chemical Classification

In the chemical classification system, the plants are classified based on the nature of the chemical constituents present in them.


Following are some main examples,


Following are examples of crude drugs containing alkaloids

  • Cinchona

  • Ipecac


Following are examples of crude drugs containing glycosides,

  • Aloe

  • Senna

  • Digitalis

  • Glycyrrhiza


Following are examples of crude drugs containing resins,

  • Benzoin

  • Tolu Balsam


Following are examples of crude drugs containing tannins,

  • Tea


Following are examples of crude drugs containing carbohydrates,

  • Acacia

  • Tragacanth

  • Isabgol

Volatile Oils

Following are examples of crude drugs containing volatile oil,

  • Clove Oil

  • Fennel Oil

  • Cardamom Oil

Chemotaxonomic Classification

This classification is based on the fact that certain chemicals occur in a specific class of plants.


  • Tropane alkaloids are present in the family Solanaceae.

Sero Taxonomic Classification

This classification system is based on the application of serology in resolving taxonomic issues.

Important Topics

Ginger | Constituents Of Ginger

Clove And Constituents Of Clove

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